My additions didn't propogate down to postfix. It looks like these are the only valid protocol restrictions:

For protocol checks, the following three RBLs can be enabled:
*Hostname in greeting violates RFC - reject_invalid_hostname
*Client must greet with a fully qualified hostname - reject_non_fqdn_hostname
*Sender address must be fully qualified - reject_non_fqdn_sender

My additions didn't propogate down to postfix. It looks like these are the only valid protocol restrictions:

For protocol checks, the following three RBLs can be enabled:
*Hostname in greeting violates RFC - reject_invalid_hostname
*Client must greet with a fully qualified hostname - reject_non_fqdn_hostname
*Sender address must be fully qualified - reject_non_fqdn_sender